1. Technical Field
This invention concerns computer systems. In particular, it relates to a computer system having a central processor arranged to poll and receive data from peripheral units.
2. Background
Computer systems as employed in the data communication field oftentimes comprise a central processor coupled with and arranged to process data collected by peripheral units. In a typical application as may, for example, be used in telecommunications, a peripheral unit sometimes referred to as a sensor is connected with various components of telephone switching equipment so that data generated by operation of the telephone switching equipment may be detected and received by the sensor. Periodically the central processor collects and records the data received by the sensor in a memory store and subsequently processes the data to prepare information such as traffic studies depicting call handling characteristics of the telephone switching equipment and customer call billing records. A central processor is usually coupled with a large number of sensors and is arranged to poll each sensor periodically and have the data received by the sensor collected and recorded in a memory store.
Each sensor typically has a small buffer used to store data received between polling intervals. Normally the size of the sensor buffer is selected to hold data received during the period of time between polling intervals. However a problem arises in that the amount of data received by a sensor varies with the operation of the equipment coupled with the sensor. For example, telephone switching equipment serving the metropolitan area of a large city oftentimes generates more traffic during the day than telephone switching equipment serving the city suburbs. During the evening the reverse may be true in that the telephone switching equipment serving the suburbs may generate more traffic than the metropolitan telephone switching systems. Even during the day and evening hours traffic handled by specific telephone switching equipment may vary in that there may be little traffic in metropolitan telephone switching equipment during the early morning hours with heavy traffic occurring during the later morning hours. In suburban telephone switching equipment heavy traffic may occur during the early evening hours with light traffic occurring during late evening hours.
When equipment coupled with a sensor generates more data during the period of time between polls than the sensor buffer can store, data is lost. If the interval of polling sensors is decreased then the efficiency of the computer system may be decreased in that more processor time will be spent in polling sensors having only a small amount of data stored in the sensor buffer.
Apparatus has been disclosed for controlling the flow of data between peripheral units and a central processor. This generally consists of modifying buffer apparatus to improve the characteristics of the buffer with regard to receiving the transmitting data. A problem arises with the prior art apparatus in that while it improves the efficiency of the buffer apparatus it does not improve the characteristics of the computer system in controlling the data flow from a number of sensors each arranged to detect widely varying amounts of input data at various times.
Accordingly, a need exists for a computer system arranged to smooth the data load offered by sensors to a central processor. A need also exists for a computer system having a central processor arranged to dynamically vary the time of polling sensors in response to the amount of data registered therein to effectively smooth the data load offered the central processor coupled with the sensors.